Comparisons of pica in-depth material performance and ablator response modeling from medli arc jet tests

The Mars Science Laboratory Entry Descent and Landing Instrumentation (MEDLI) project performed extensive arc jet tests for development, qualification, and calibration of instrumented heat shield plugs. The arc jet test results are entered into a comprehensive database so that broad trends across the test series can be compared. Using the near- surface thermocouple measurements as a boundary condition in numerical simulations, comparisons are made with other thermocouple measurements taken deeper within the TPS test article. The temperature prediction accuracy is quantified for the tested material and material response code and is found to be highly dependent on the distance between the boundary condition thermocouple and the deeper, reference thermocouple. It is found that predicted temperatures are consistently greater than measured values indicating the PICA material model is generally conservative for in-depth temperature predictions.